McDonnell XHJH Whirlaway
1946 prototype helicopter model by McDonnell Aircraft Corporation
The McDonnell XHJH Whirlaway, a.k.a. McDonnell Model 37, is a 1940s American experimental transverse-rotor helicopter designed and built by McDonnell Aircraft Corporation for the United States Navy and was the largest helicopter at the time, as well as the first successful twin-engined twin-rotor helicopter in the world.
Design and development
In 1944, the United States Navy issued a requirement for a large rescue helicopter with capacity for ten occupants. The design was originally designated XHJD-1; shortly after flying it was re-designated the XHJH-1. It was derived from the single-engined, twin rotor Platt-LePage XR-1. James McDonnell had invested in that company in 1942 and some of his engineers had been working there, gaining experience of helicopter design and production techniques. McDonnell took control of the company in June 1944. The XHJH-1 first flew two months later. It had twin side-by-side 46 ft (14 m) rotors at the end of pylon wings which turned in opposite directions. Each rotor was powered by a 450 hp (336 kW) Pratt & Whitney R-985-AN-14B Wasp Junior engine.
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This entry incorporates text from “McDonnell XHJH Whirlaway” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.